Tesla has created some serious buzz with its cars, and its new solar roof. But for many homeowners, the question remains: How affordable are these roofs?

As of August of this year, that question has been answered. Tesla now has an online calculator on its website where customers can get an estimate for their roof.

Using Consumer Reports (CR) cost analysis which determined that, for a Solar Roof to compete with a conventional asphalt roof, it should not cost more than $24.50 per square foot for an average-sized American home – based on the estimated cost of 30 years of electricity – Tesla said it beat the upper limit CR identified by nearly 11 percent, coming in at $65,550 ($21.85 per square foot) for the same example house.

Both CR’s calculation and Tesla’s include the cost of Tesla’s Powerwall battery, which is necessary for a home to store the energy generated by the tiles.

The online cost calculator also uses your address to determine the ratio of solar to non-solar tiles your house would need to get 100 percent of your energy from solar, then deducts the upfront cost of the roof and the Powerwall battery from the cost of what you’d otherwise spend on energy over 30 years. That estimate is based on the price of electricity where you live, assuming a 2 percent increase in your utility bill each year.

The estimate also factors in the 30 percent Federal Solar Investment Tax Credit, and then matches the 30 year timeframe with warranties on both power generation and weatherization for the Solar Roof.

When financed, the cost of the Solar Roof is designed to be recovered in the energy savings a customer can expect every month. On a 2700 square foot house, for example, the cost of a solar roof and Powerwall, plus installation would cost $45,400. However, with the Federal Tax Credit, of $12,500, the actual cost is brought down to $32,900. Calculating the energy savings over 30 years at $46,800, the total savings over the course of 30 years comes to $13,900.

While at first glance, Tesla’s Solar Roof seems to make sense, homeowners should also consider factors such as the state they live in, their state’s net metering policy (which will allows them to sell back power to the utility company at the same price that they purchase it), the length of time they want to stay in their home, and the age of their roof now.

This article is brought to you by ASAP Roofing, a national roofing company that specializes in hail damage, roofing restoration and weatherization. ASAP has offices in Dallas, Texas, and Denver, Colorado.